Single ram balers typically comprise a horizontal compaction chamber in which a platen mounted to a press ram moves horizontally, forward and backward, to compact recycled materials provided in the compaction chamber. The recycled material is generally fed in the compaction chamber by gravity, trough a feeding opening defined on the top of the compaction chamber.
Upon compaction by the actuated platen, the compacted material moves toward an extrusion channel mounted to an outlet end of the compaction chamber. The extrusion channel is generally defined by a fixed bottom wall, a pivoting, adjustable, top wall and a pair of spaced-apart, pivoting, sidewalls. Each wall defining the extrusion channel includes a first, inlet end and a second, opposed, outlet end. The inlet end of the pivoting side and top walls are hingedly connected to the outlet end of the compaction chamber. The second outlet end of these pivoting walls is displaceable between an open and a close position, by way of actuator means. The actuator means allows the adjustment of the size of the extrusion channel at the outlet end, therefore increasing the pressure over the compacted recycled material as it is funnelled trough the extrusion channel
Because fed material has often a low density, has a lower friction factor, is loose or has a larger size than the actual size of the compaction chamber, the compaction efficiency can be reduced. The prior art describes two general type of devices designed to overcome such problems. The first consists in a shear blade assembly including a first, fixed, blade mounted to one edge of the feeding opening of the compaction chamber and a moving blade, mounted to a top end of the platen. Upon frontward progress of the platen in the compaction chamber, the fixed and moving blades collaborate to guillotine the material lodged in the feeding opening. The fixed blade is generally V-shaped to increase cutting efficiency.
The efficiency of the single ram balers of the prior art having shear blades assembly tend to be reduced since the production of bales typically requires several back and forth movement of the platen to obtain the desired amount of material in the extrusion channel, especially when such material consists in low density material such as fluff paper, plastic containers and the like. Further, shear blades tend not to be of particular assistance in pre-compaction of recycled material of smaller dimension such as plastic and metal containers or smaller sheets of paper and the density of the bales produced therefrom tend not to be satisfactorily uniform (i.e. the compacted material tend to denser at the bottom of the bale than at the top thereof). In addition, some material, such as newspaper, tend to be very difficult to sever or shear, therefore increasing the power required for reciprocation and the energy consumption of the baler.
The second type of device designed to improve compaction in the compaction chamber generally consists of preflap arrangement. Briefly, the recycled material is fed into the compaction chamber through the opening. A preflap is actuated to close the feeding opening, forcing the material stuck in the feeding opening into the compaction chamber. This configuration tends however not to be efficient when the material to be compacted comprises large pieces of material such as, for instance, boxes of corrugated cardboard. Indeed, large recycled material tends to jam the preflap assembly and require the baler to be shut down for manual removal of stucked material.
It would therefore be advantageous to be provided with a single ram baler that overcomes at least one of the drawbacks associated with previous single ram baler configurations.